Re: Alternative strategies

From: John K Clark (jonkc@att.net)
Date: Sat Aug 16 2003 - 10:16:34 MDT

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    "Robert J. Bradbury" <bradbury@aeiveos.com>

    > Ok, so you get great resolution -- what in the blazes are you going to
    > use to "imprint" the image on? All photons above UV energy levels will
    > cause bond cleavage

    I'm not quite sure what you mean. I would think if you didn't want to build
    a specific structure but just record information then bond cleavage is
    exactly what you'd be aiming for; if a bond has been broken then it must
    have encountered a photon, if it is still intact then it has not. I couldn't
    find much about Gamma Ray Holography but a lot has been done with the X ray
    variant and atomic resolutions have been achieved, see below.

    [F28.04] X - Ray Holography with Atomic Resolution
    Miklós Tegze (Research Institute for Solid State Physics, H-1525 Budapest,
    P.O.Box 49, Hungary)

    In the conventional diffraction experiments only the intensity of the
    scattered radiation is recorded, its phase is lost. In holography [1], the
    scattered radiation is mixed with a reference wave and the resulting
    interference pattern is recorded. The hologram contains both the intensity
    and the phase information and the three dimensional image of the object can
    be reconstructed. The most important limitation of this imaging technique is
    the spatial resolution, which is given by the wavelength and/or by the
    source size. In the last decade the introduction of soft x-ray instead of
    visible light tremendously improved the resolution which reached a few
    hundred angstrom [2]. An other line in holography, based on the inside
    source concept, was suggested recently [3]. We have applied this concept for
    the case of fluorescent x-rays emitted by a single crystal. We were the
    first to demonstrate theoretically [4] and experimentally [5] the
    feasibility of x- ray holography with atomic resolution. We have recorded
    the holograms of different crystals and successfully reconstructed the three
    dimensional order of the atoms. \bigskip [1] D. Gabor, Nature \bf161, 777
    (1948). \hfil [2] M. Howels, C. Jacobsen, J. Kirz, R. Feder, K. McQuaid and
    S. Rothman, Science \bf238, 514 (1987). \hfil [3] A. Szöke, in Short
    Wavelength Coherent Radiation: Generation and Applications, T. Attwood, J.
    Booker (eds), AIP Conference Proceedings No. 147, New York (1986). \hfil [4]
    M. Tegze and G. Faigel, Europhys. Lett. \bf16, 41 (1991). \hfil [5] M. Tegze
    and G. Faigel, Nature \bf380, 49 (1996).\hfil

       John K Clark jonkc@att.net



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